Steam-boiler furnace



(N0 ModeL) I F. LEADBEATER.

STEAM BOILER FURNACE. No. 326.877. Patented Sept. 22, 1885.

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UNITED STATES PATENT OFFICE.

FREDERICK LEADBEATER, OF DETROIT, MICHIGAN.

STEAM-BOILER FURNACE.

SPECIFICATION forming part of Letters Patent No. 326,877, dated September 22, 1885.

Application filed June 23, 1885.

To all whom it may concern:

Be it known that I, FREDERICK LEAD- BEATER, of Detroit, in the county of \Vayne and State of Michigan, have invented certain new and useful Improvements in Steam-Boiler Furnaces; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form part of this specification, in which Figure 1 is a side view of a steam-boiler furnace having my invention applied thereto, the door of the hot air-chamber being removed to show the steam-jet director. Fig. 2 is a front View of the same, partly in section. Fig. 3 is a detail of the jet-director.

This invention relates to improvements in steam-boiler furnaces or generators, and is especially designed for use with generators in which refusecoal or screenings is used as fuel; and it has for its object to provide means whereby a current of hot air, taken from the escape-fiue or smoke-drum of the generator and mixed with steam from the steam-dome, may be automatically forcibly injected beneath and through the fuel on the grate, thereby increasing the heat in the furnace, with a small amount of fuel, all of which will be fully understood from the following descrip tion, when taken in connection with the annexed drawings.

A designates the body of a steam-boiler of the well-known kind, or of any desired construction, provided with steam-dome a and escape-flue or chimney a for the products of combustion. The boiler is supported and partly inclosed by a wall of brick, B, which also forms the sides and rear end of the furnace.

O is the grate or fire-bed of the furnace, situated at the end of the wall B beneath the free end of the boiler A. This grate may be of any suitable kind 5 but is preferably a perforated bed suitable for holding very fine coal or screenings. D is .the bridge-wall at the inner end of the grate. The face of the furnace is of brick, or of the usual metallic kind, and is provided with doors 1) opening into the fire-chamber above the grate, for replenishing the fuel thereon, and a door, I), beneath (No model.)

the grate for allowing access to the ash-pit. These doors should all be closed air-tight during the operation of the furnace, and the wall B should be built air-tight around boiler A.

E is an air-chamber or chest secured to the wall B outside of the fire-box, provided with a door, e. The chest E may be closed airtight from the outside; but opens into the tirechamber beneath the grate through a number of pipes, F, secured in a partition, B, in wall B, or in the wall itself, and projecting a short distance into air-chest E and into the firechamber, as shown.

G is a pipe which leads from the flue a at a suitable point down to the chamber E, into which it opens so as to discharge heated air and products taken from the line into the chest near the ends of pipes F. This pipe may be provided with asuitable valve for regulating the quantity of products passing into chamber E.

H is a steam-pipe leading from dome a into the air-chest E for the purpose of admitting steam therein, and provided with a valve, h, for regulating the supply of steam thereto. The pipe H connects by a suitable coupling with a steanrdirector, J, removably secured in chamber E, and serving a purpose hereinafter explained. The director J consists of a main vertical pipe, 3', of same diameter as pipe H, provided with a series of horizontal arms or pipes, j, of smaller diameter, adapted when the director is in position to be directly opposite the ends of horizontal rows of pipes F. The arms j open into pipe j and receive steam therefrom. Their outer ends are closed, and their inner faces are provided with a number of perforations, j", smaller in diameter than pipes F, each perforation being directly opposite the end of a pipe, F, and adapted to jet the steam and air into and through pipes F beneath the bed of fuel on the grate when in operation.

I designates a pipe, the lower end of which entersthe fire-chamber above pipes F, and its outer end extends upward and is provided with a steam or pressure gage, I, for ascertaining the amount of steam or pressure in the fire-chamber.

The operation of the invention is as follows: After a fire has been kindled on the grate and steam begins to generate in the boiler the valve in pipe'G is opened and the doors of the furnace and air-chest tightly closed. Steam is now admitted through pipe H, enters director J, and jets through the perforation j into pipes F. The jets of steam will force the air in chamber E into the fire-chamber through pipes F, thereby creating a partial vacuum in the air-chest E. Heated air will be drawn down through pipe G to replace the removed air in the chest. The jets will continue to withdraw the heated air and products through the pipes F into the fire-chamber and force them into and through the bed of fuel on the grate. As the pipe G draws the heated air from the escape-flue of the furnace any particles of carbon carried off in the products from the fuel will be drawn back through pipe G into the air-chest, and thence expelled back into the furnace and into the incandescent fuel, this operation being repeated until all, or nearly all, the carbon in the fuel is consumed, obviously effecting a great saving of the same.

The force of the currents of air and steam passing through the perforations of the grate will agitate the fine particles of fuel and prevent their smothering or baking, thus allowing very fine coal-dust or screenings to be utilized as fuel. A small opening may be made through one of the doors, suitably closed, through which the condition of the fuel may be noted.

When it becomes necessary to replenish the fuel on the grate, the valve in pipe H is closed and fuel supplied through one of the doors b. When the door is closed, the steam may again be turned on.

Having described my invention, I claim- 1. The combination of the boiler, the firechamber and ash-pit separated by a finelyperforated grate capable of holding charges of coal-dust, and both fire-chamber and ashpit capable of being closed hermetically, the

chamber E opening through pipes into the side of the ash-pit, receiving air only from the escape-flue and capable of being hermetically closed, and the pipe from the steamdome of the boiler running into the chamber E and arranged to drive jets of steam into the ash-pit, whereby the air is drawn from the escape-flue mixed with smoke particles, substantially as specified.

2. The combinatiomwith asteam-generator, of an air-chamber opening into the furnace beneath the grate through a series of short horizontal pipes, F, and receiving heated air through a pipe, G, from the escape-flue of the furnace, and a jet-director, J, composed of a main pipe, 9, and a series of horizontal pipes,

j, provided with perforations or jet-apertures directly opposite the ends of pipes F, and a s1 eam-pipe, H, provided with arvalve conveying steam from r the boiler to the director J, substantially as and for the purposes described.

3. The combination, with asteam-boiler furnace provided with a perforated grate and hermetically-closing doors, and an air-chamber also provided with a hermetically-closing door and opening into the furnace beneath the grate through a series of pipes, F, secured in the wall or partition in the wall of the furnace, of a pipe, G, conveying heated air and 

